Relay



Oct. 10, 1961 Filed Dec. 31, 1956 C- J. FITCH ETAL RELAY 5 Sheets-Sheet 1 INVENTORS. CLYDE J. F/7'CH HAPPY L4 DUVN A TTORNE) Oct/'10, 1961 c. J. FITCH EI'AL 3,004,126

RELAY Filed Dec. 51, 1956 5 Sheets-Sheet] INVENTORS. g CLYDE J. FITCH HAPPY L. DUNN BY MM ATTORNEY Oct. 10, 1961 c. J. FITCH ETAL 3,004,125

RELAY Filed Dec. 31, 1956 5 Sheets-Sheet 3 0, a g o, INVENTORS.

\ CLYDE J. FITCH HARRY L. DUNN BY Z Z r: M

ATTORNEY United States Patent i 3,004,126 RELAY Clyde J. Fitch and Harry L. Dunn, Endicott, N.Y., assignors to International Business Machines Corporation, New York, N.Y.,' a corporation of New York Filed Dec. 31, 1956, Ser. No. 631,744 1 Claim. (Cl. 200-166).

The present invention relates to a relay and, in particular, to a relay that is actuated by an electro-adhesion system operative of a large number of contacts either on a cyclic or on a hold basis. 1 v

In many relay applications there is need for high speed 3,004,126 Patented Oct. 10, .1 961 between the drive and driven members is lower than in and for low current consumption for actuation. These operating criteria have been difiicult to attain with the conventional inductance type relays. In many of the prior art relays, high speed is basically impossible because of the mass necessarily involved, which must be accelerated each time the relay is actuated, and because of therelativelylarge time element in hysteresis curves. A further defect of the prior art has been that it has been difficult to renew the contacts when such have become bad. This is particularly true where the contacts have been piled, that is, Where there are a plurality of contacts or circuits made or broken by actuation of the relay.

Thus, it is an object of the present invention to construct a relay having very light weight moving parts.

Another object is to provide atrelay free from contact bounce.

A further object is to construct a relay in which the contacts maybe easily replaced.

A still further object is to construct a relaythat is electro-adhesively operated.

Another, and more inclusive, object of the invention is to construct a relay that will operate rapidly as compared with prior art relays.

Another object is the construction of a relay requiring relatively small currents for its operation as compared with prior art relays.

Other objects of the invention will be pointed out in the following description and claim and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode which has been contemplated of applying that principle.

In the disclosed form of the invention, the relay contacts are actuated by a constant speed rotary drive through an electrostatic clutch of the kind disclosed in copending applications Serial No. 556,644 (now abandoned) and Serial No. 556,676 (now Patent No. 2,923,390, issued February 2, 1960), both filed December 30, 1955, and in US. 2,025,123, issued December 24, 1935. The clutch band shown in these prior applications is extended to receive in insulation the end of one leg of a hairpin which acts as a transfer lead when the band is moved between limits under the actuation of the electrostatic clutch or of a spring which returns the band from its clutch actuated position. I I 1 t The construction outlined above is shown'in the accompanying drawings, in which:

FIG. 1 is a cabinet view of a relay unit embodying the the other disclosure.

In the cabinet view of FIG. 1, mechanical power is furnished to the electrostatic clutch of the relay by a drive gear 11 which is continuously rotated during the periods when the relay may be called upon for operation. The drive gear 11 is in mesh with and drives a driven gear 12, preferably of insulating material, which is mounted for rotation on a shaft 13 secured between brackets 14, 15 which are part of the frame of the relay. Secured to the driven gear 12 is a hub 16 which also rotates on the shaft 13. (The shaft, brackets and hub are preferably of brass.) An electro-adhesive material 17 is bonded to ,the peripheral face of the hub 16 and is formed as a sleeve with a cylindrical outer face which acts as a clutching surface for and with a surface portion of a clutch band 19. The clutch band is preferably of stainless steel. The composition of the electro-adhesive material 17 is disclosed in the above mentioned copending application Serial No. 556,676. The contacting faces of the band and the electro-adhesive may be treated in the manner disclosed in either of the above mentioned applications.

The band 19 is wrapped around the hub for a considerable portion of its periphery. The drag which the rotating hub exerts on the band is greatly increased by the application of a voltage potential between the band 19 and the electro-adhesive material 17. The band is maintained in contact with the electro-adhesive material by a spring 21, 22 at either end of the band. One (22) of the springs is stronger than the other (21) to counteract the frictional pull on the band when there is no potential applied.

Furthenthis heavier spring 22 may be considered to bias the clutch band 19 to a home position, the position of the band shown in FIGS. 2 and 3.

The relay is formed with an insulating end block 23 to which are secured the clutch brackets 14, 15, the near bracket 15 being the same as the far bracket 14 but mostly being broken away in the showing of FIG. 1. The upper end of the end block 23 is bifurcated to receive and hold a pin 24 which serves as an anchor for the weaker spring 21, and to receive and hold one end of an insulating central mounting bar 26. Medially of the length of the mounting bar are spacedapart hairpin support pegs 27 which pass through the bar 26 and extend outwardly on each side thereof to enter on each side a contact base block, left 28, right 29. Each of the two base blocks on its inner face is spaced from the mounting bar 26 by one of two spacerstrips 31. Each spacer strip provides room for a series of U-shaped hairpins having a short leg 32 and a long leg 33. Two hairpins are hung on each of the pegs 27, one on each ,sideof the mounting bar. The spacer strips hold the hairpins down on the pegs and each strip is thick enough so that the legs of the pins are free to move in the space on each side of the bar formed by a strip spacing a base block from the bar. Spaced along the outer face of each of the base blocks, the outer facebeing the one away from the mounting bar, and transversely of the length of the blocks is a row of the shanks 34 of contacts 36, 37, 38, the contact portion being at right angles to the shank and spaced from and under the base against which the shank is placed. 'The inner ends of the contacts in the left row are spaced from the ends of those in the right row. The shanks in each row of shanks on each side of the mounting bar are held in spaced apart position against their base block by a clamp plate 40, 41. The upper end of each shank 34 projects above the mounting bar 26 and this end serves as a circuit terminal. The bar, strips, bases and plates are held together by bolts 42 and they all extend at right angles from the end block. Each hairpin straddles one (37) of the contacts and is biased to have each of its legs bear against a contact 36, 38 adjacent the one which it straddles but does not contact.

This is the home or open position and condition for the hairpins.

Between the clutch and the heavier spring 22 the clutch band 19 extends generally parallel to and spaced below the mounting bar 26 and rows of contacts, and in position for the longer leg 33 of each of the hairpins to extend through but not contact the sides of a separate hole 43 in the band, which hole is provided for each of such legs. During the operation of the relay the shorter leg of the hairpin contacts only the one input or common contact 36, while the longer leg is moved from the open or home contact 33 to the closed or actuated contact 37. Thus, the contacts and their shanks may be considered to be divided into groups of three, each such group being functionally related to one of the hairpins. While the longer leg of each hairpin extends through a hole 43 in the clutch band, it does not contact the band but is insulated therefrom by making such holes large relative to holes 44 in an insulating strip 46 secured to the clutch band, each role in the insulating strip being coaxial of a hole in the hand and being of a size to fit the hairpin wire snugly so that it is confined against bounce or vibration. This is a closed pair connection. Each end of the clutch band has secured thereto an insulator, one (4'7) at the end adjacent the clutch to which the lighter spring 21 is hooked and another (4-3) at the hairpin end to which the heavier spring 22 is hooked, these insulators electrically insulating the band from the springs. A guide post 49 extends through the latter end insulator 48 in a slot 51 therein to maintain that end in proper alignment and to limit the longitudinal movement of the band to that desired. The guide post 49 is mounted on a base 52 which also carries a bracket 53 to which one end of the larger end spring 22 is secured. This block is held in place by a pair of runners d, 55, one along each outside lower edge of the relay with an arm extending upward at the right to fasten to the right end of the mounting bar 26. The right and left sides of the relay are symmetrical to each other with the exception of the driven gear being on the left side.

The showing in FIGS. 2 and 3 is illustrative of the circuit connections which may be made to a relay of this type for actuation of the clutch and for the actuation of auxiliary circuits to be controlled by this type of relay. In FIGS. 2 and 3 only three hairpins and their contacts and circuits have been shown. One of these hairpins is used for controlling the circuit for actuation of the clutch and the other two are used in controlled circuits.

FIG. 2 illustrates a circuit for the control of the clutch so that its operation will be periodic or cyclic when power, or a source of potential, is connected in the energizing circuit and when the clutch hub 16 is continuously and unidirectionally rotated. In this circuit the left hand hairpin 201 has been shown and used for controlling the operation of the clutch. Power is delivered to the clutch from, say, the positive terminal of a battery 202 under the control of a switch 203 through a power lead 204 to the common contact 36 of the hairpin 201, through the hairpin to the open or home contact 38', through a clutch lead 206 to the hub 16 of the clutch. The lead 206 to the clutch hub may be to the brackets 14, and through the shaft 13 to the hub, or the lead 206 may be to a brush 207 bearing directly on the hub 16. From the hub the power passes through the semi-conductor sleeve 17 to the clutch band 19 and then to a brush 208, or flexible pigtail, to a ground connection 209 back to the battery. Connected to the clutch lead 206 is one side of a condenser 211 which has its other side grounded. With a potential applied to the clutch semi-conductor and the clutch band and across the plates of the condenser 211, the condenser will be charged and the band 19 will move with the rotating hub and semi-conductor in the direction indicated by the rotational arrow. This motion of the band will carry the long log 33 of the hairpin from the home contact 38 to the actuated contact 37, and the charge on, the condenser 211 will maintain the potential of the clutch lead 206 to the hub while the long leg 33 of the hairpin is transferring from the home contact 38 to the actuated contact 37. A lead 212, having therein a resistance 213, is connected between the actuated contact 37 and the band 19 through the band brush 208 to reverse or change the charge on the band so that there is no potential across the clutch. This releases the clutch to allow the stronger spring 22 to return the band and the hairpins to their home positions where contact is again made with the positive potential to cause the rotating hub again to move the band for another cycle.

The value or design of the condenser 211 and the resistance 213 is based upon the semi-conductor 17 having a resistivity within the general range of 10 to 10' ohms per cubic centimeter and an operating current of the order of milliamperes at 200 volts. The time of each cycle of operation of the relay may be varied by changes in the values of the condenser and/or the resistance. The time of a cycle of operation may be in the order of milliseconds.

The circuits associated with each of the controlled circuit hairpins 216 are the same, and the reference numbers applied to these hairpins and their circuits are the same. Only one circuit will be described. A common lead 217 is connected to the common contact 36, while the home contact 38 has its home lead 218 and the actuated contact 37 has its actuated lead 219. With this circuit arrangement, the circuit 217-218 may be opened and the circuit 217219 closed periodically and alternately, or either circuit alone may be periodically opened and closed.

FIG. 3 illustrates a circuit for the control of the clutch so that its operation will be intermittent and will operate only in a half cycle as power or a source of potential is connected in or disconnected from the energizing circuit, and when the clutch hub is continuously and unidirectionally rotated.

The circuits of FIG. 3 differ from those of FIG. 2 in only one respect, and that is in a holding lead 321 from the actuated contact 37, having therein a resistance 322, being connected to the clutch lead 206 instead of to the band brush 208. Those other parts which are the same as in FIGS. 1 and 2 have retained the reference numerals previously used.

In the operation of the FIG. 3 control circuits, closing of the control switch 203 will move the long leg 33 of the hairpin 201 to the actuated contact as previously described; then power will continue to be delivered to the clutch through the holding lead 321, having therein the holding resistance 322, and the clutch lead 206. This causes the relay parts to remain in their actuated positions as long as the control switch 203 remain closed, the actuated position being that of the long leg of each hairpin in contact with its actuated contact 37. The parts will return to home position when the control switch 203 is opened. The holding resistance 322 is of a value which will reduce the voltage applied to the clutch to prevent over-heating of the clutch parts, particularly the semi-conductor 17, and of a value which will allow slippage between the semi-conductor 17 and the band 19 when the parts are in the actuated position.

The operation of the controlled circuits is the same as that previously described in connection with FIG. 2.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claim.

What is claimed is:

A relay, comprising: an elongated mounting bar with opposite sides, a row of pegs, each of said pegs extending thru and having an end outwardly of each of said bar sides whereby there is formed a row of peg ends along each of said bar sides; a straight spring wire'having therein a single bend, said bend shaping said wire in the form of a hairpin spring having legs of unequal lengths, and such a hairpin being hung on each of said peg ends adjacent said bar so that the inside of said bend of each hairpin contacts such a peg end and so that there are two rows of said hairpins and their legs and so that all the legs of 'a'said row of hairpins are coplanar in a plane parallel to a said bar side, a spacer strip contacting the bends of each row'of hairpins to confine said hairpins to their pegs; a base block engaging each spacer strip, receiving therein a row of said peg ends, and limiting movement of said pins along said pegs; a clamp plate along each of said sides and in opposition to each of said blocks; a plurality of L-shaped conductors formed in two rows, each conductor having a shank and at right angles thereto a contact portion, the shanks of all the conductors of a row being parallel, coplanar, and held between and transverse one of said blocks and one of said plates, and each shank extending from its said block and plate, the contacts of said rows being in a plane intersecting all the legs of said hairpins and each row of contacts being between the rows of said shanks, and each leg of each hairpin being between two of said contacts whereby contacts and hairpin legs alternate in a row and the spring action of each such shorter legs, and adapted upon actuation to move each I said longer leg from one of said contacts to another.

References Cited in the file of this patent UNITED STATES PATENTS 506,297 Alexander Oct. 10, 1893 960,654 Lovejoy June 17, 1910 1,647,792 Gent u Nov. 1,1927 2,039,568 Tamsitt May 5, 1936 2,148,482 Lorenz Feb. 28, 1939 2,208,125 Feingold July 16, 1940 2,282,066 Lake et a1 May 5, 1942 2,365,738 Williams Dec. 26, 1944 2,417,850 Winslow Mar. 25, 1947 2,573,514 Turner Oct. 31, 1951 2,735,909 Floyd et al Feb. 21, 1956 2,783,330 Casey Feb. 26, 1957 2,790,939 Horlacher Apr. 30, 1957 2,805,301 Shaw Sept. 3, 1957 FOREIGN PATENTS 438,860 Germany Dec. 28, 1926 Netherlands Aug. 16, 1954 

